


Music, a Language and Everything

by einsKai



Category: IDOLiSH7 (Video Game)
Genre: Aliens, Alternate Universe - Space, Arguing, Bickering, Developing Relationships, Gaku gets annoyed a lot, GakuTenn Jesus Kai breaking the bread once again, Humor, M/M, Musician!Tenn, Pre-Relationship, SCIFI AU, Science Fiction, Scientist!Gaku, Space Stations, Xenology is alien science btw, and also fall in love even though it's not explicitly mentioned it's the intention, it's mostly about the language, they don't like it but they gotta work together and get closer, written for 898 week, xenology
Language: English
Status: Completed
Published: 2019-09-15
Updated: 2019-09-15
Packaged: 2020-10-19 08:31:34
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 4,280
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/20654240
Author URL: https://archiveofourown.org/users/einsKai/pseuds/einsKai
Summary: “‘Moon’s Angel’, superstar at age eighteen” sounded better than “mars’ promising young xenologist Yaotome Gaku does very important and super interesting research to find out more about those weird slimes from planet 8Da9H.”And now they’d have to work with each other. Shit.





	Music, a Language and Everything

**Author's Note:**

> Hellolo, welcome to my first fic for the GakuTenn week! I won't be writing something for every day, because my quality standards won't let me, but I have at least one other work almost finished! 
> 
> This one is for the AU prompt, and I really went all out with this, there is much more thought and depth to this AU than it says in the fic. I have some notes I wanna share in the end notes, so please read to the end :D
> 
> Look at the [GakuTenn Week's](https://twitter.com/898week) account on twitter to check out other people's works for it!
> 
> Have fun reading! 
> 
> -Kai

“I can’t believe we’re doing this”, Gaku mumbled.

The scientist was standing in attendance for the arrival of a spaceship. Usually this specific ship stopped by their space station every fortnight to deliver supplies, rations, parts, instruments, all kind of things they needed at the research plant. For that they didn’t have to stand in the hangar and wait. No, today was different.

_“We’re getting someone to help with figuring out communication”, the captain had said without waiting for Gaku to greet them after entering his lab. No wonder. Gaku never greeted anyone who stepped into his lab._

_Gaku had hummed in acknowledgement, even though he hadn’t actually been listening. He had been looking over the data the last tests had brought. Nothing new. Absolutely nothing new. Shit._

_“He is a musician. I’m transmitting his profile, so you can prepare working with him.”_

_With a flick of their wrist a holographic image of a young man on a red carpet appeared in front of Gaku’s data. He was well dressed in the picture, and was smiling lightly, one hand raised in a tentative wave at the cameras._

_“That’s just a kid”, Gaku had grumbled, because actually he _had_ been listening and just didn’t want to show it. “I’m not sharing my work with a _kid_.”_

_“You will”, the captain had said. “It’s an order. You’re both the best in your area of expertise. Geniuses like you are loners, but this time you gotta band together so you can produce genius-like results.”_

_“I’m not working with him.”_

_A certain twinkle had appeared in the eyes of the captain. “You know”, they had said. “In the eyes of someone my age, you, too are nothing but a young kid.”_

_“Well in _my_ eyes I’m an adult though.”_

_“Sure sure, adult-Yaotome Gaku-kun. If you aren’t working with Kujou Tenn, then you better start learning how to sing.”_

_With that the captain had left him alone, file of his future co-worker still open on his holo-display._

So now he was here to greet this Kujou Tenn kid. To welcome him on board. Hah.

The hatch opened, lowered, and down there came the kid, whose file Gaku still hadn’t closed, ever since the captain left it with him. For no reason, obviously. He had just forgotten to close it.

The boy stepped down the gangway like he was a prince entering his castle. And Gaku already felt his eyebrow twitch in annoyance.

With a neck craned in obvious curiosity and observation shining in his eyes, the newcomer took in his surroundings. It was painfully obvious that he had never been on a space station. Hell, this was probably his first time in space too.

Behind him, worker bots began the heavy lifting of the boxes full of equipment and supplies. He stepped aside to let them pass through, never stopping his scan of the station.

His gaze arrived at the crew, the few people staying in this station in the orbit of planet 8Da9H. The captain, a doctor, a few scientists (a biologist, a geologist, a physicist, a chemist, and Gaku, their xenologist). They were understaffed, if one thought about it rationally, there was no way a team of seven, or now eight, would be able to categorise an entire planet and figure out a way to communicate with the native alien species, but that wasn’t Humanity’s Space Bureau’s concern.

At least this man was here now.

Kujou Tenn, musical prodigy back on his moon colony, a rising star on earth as well, and already known throughout the galaxy. Gaku knew that if someone showed him a song of Tenn’s he would recognise it, even if he never consciously listened to one.

And that very Kujou Tenn’s eyes were trained on him right now. It was as if he was scanning him. It was his damn file, Gaku thought. Someone had given Tenn his file, and he was making fun of him right now. 

“‘Moon’s Angel’, superstar at age eighteen” sounded way better than “mars’ promising young xenologist Yaotome Gaku does very important and super interesting research to find out more about those weird slimes from planet 8Da9H.”

And now he’d have to work with the arrogant brat. Shit.

Tenn smiled a smile that was as bright and nice as it was cold and fake.

“Hello. My name is Kujou Tenn, musician. I’m looking forward to working with you.”

And Gaku knew that there were some hellish months awaiting him.

☆☆☆

“The food here is horrible”, Tenn sighed as he sat down next to Gaku. As if he wanted to make conversation. Or friends. Gaku made room unconsciously, even though he _really_ didn’t want to be or do either of these things with Tenn.

“We’re in the middle of nowhere and have to get by”, he grumbled. “Get used to it.”

Tenn looked at him as if he was one of the Jinglians of planet 8Da9H.

“Alright then”, he said and began nibbling on the bread that had been frozen until a few minutes ago. The heaters worked very well, and thanks to the invention of an artificial gravity generator a few decades ago, it wasn’t necessary to keep food that couldn’t damage instruments with flying crumbs anymore. It was relatively normal food actually, though of course it was a bit monotonous. It was like hospital food, his grandfather had said. Not that his grandfather had actually ever been to a hospital, but he had heard about them from a customer who had an older relative who had been to one of the last hospitals on earth as a child. Luckily every doctor could heal pretty much every sickness or wound with the instruments humanity had developed as of now.

Anyway, Gaku shook those unnecessary thoughts away, he didn’t really care about the food here, as long as he got to eat something nice like soba once in a while, and if it fuelled him enough to continue working. Other than that spoiled brat apparently.

Only after he had already returned to his lab that he had to share with Tenn now, it occurred to him that Tenn had maybe been trying to start an actual conversation with him, by starting with small talk about food. He had internally mocked him about that, before he even responded and therefore killed any kind of talk before it even could set root.

But what could he do if that annoying kid didn’t try any actual good conversation starters and instead complained about his food? On the second day only as well.

It wasn’t Gaku’s fault at all.

Hmpf.

☆☆☆

Gaku was _fuming_. It was the day they’d start working, finally, after Tenn’s way too long introduction period. Seriously, did it take Gaku thirteen days and eleven hours to finish his first phase on the station? Of course not, because he was actually trained to live and work in space, unlike the little musician, so comparing them in this aspect wasn’t only useless, but also unfair. But Gaku ignored that in favour of his annoyance.

Still, he was fuming because he had decided to start the presentation of his work with the specific biology and molecular structure of the slime-like Jinglians they were trying to communicate with.

He could’ve started with something interesting, like their cities, all perfectly fit for the elastic bodies and slimy attributes of its inhabitants. The planet had comparably low gravity, slightly stronger than the earth’s satellite, the moon, so about what Tenn should be used to outside of artificial gravity fields. The Jinglians were taller than the average human, even towering over the captain, who was an exceptionally tall person, even without the added height from their special leg prothesis that made them well over two metres tall when they wore it.

The city looked like a technologically advanced and overly large playground because of all the slides that the Jinglians used to move from A to B, and it was incredible.

Through communicating with images and gestures, they had gotten permission to set up a camera in the city centre. It streamed all day and night. Gaku loved watching the hustle and bustle of the Jinglians using the slides they had installed everywhere, and he had spent hours studying their behaviour and architecture.

What fascinated him the most was the sound. There was a constant humming in the air from the thousands and thousands of conversations being sung and hummed throughout the entire city.

_That_ was interesting.

But _no_, Gaku was petty and wanted to bore Tenn out of spite, so he had decided to start with the driest and boring part, talking about the anatomy, biology, and the flesh sample they had gotten in exchange for one of their own.

And of course it had backfired, and Gaku was bored _himself_ now! Damn it. Tenn was so annoying.

“Yaotome Gaku”, Tenn raised his hand as if he wasn’t the only other person in this room. “If I got this right, then the Jinglians take in sound over their skin, where the soundwaves create ripples. In other words, their hearing works differently, as they don’t have a specific organ for it, but _are the organ itself_. Correct?”

Gaku nodded.

“Then why did you take four hours to say something I just summarised in 17.34 seconds?”

Gaku wanted to shatter his remote controller on the floor, but he’d have to file a report and it would be a lot of work to get it replaced, so he didn’t. But he really wanted to.

He decided not to answer and changed to the next slide.

☆☆☆

“So this is one of the Jinglians?”, Tenn asked.

They had flown down onto planet 8Da9H, right outside the city they were in contact with. Today was the first time Tenn would actually be confronted with a Jinglian.

“Yes”, Gaku answered. “This is the one we’ve been communicating with. They’re really good at interpreting human facial expressions, gestures, and the pictures we show them to communicate.”

Tenn nodded and bowed down in front of the aquamarine coloured slime, to greet them.

The note they sang as a greeting was as solemn as always.

“Ah”, Tenn mumbled. “Rust Green.”

“Rust… Green?”, Gaku repeated, unsure if he had misheard.

“The tone”, Tenn said, as if it was the most natural thing in the world and imitated the exact tone that the Jinglian had just made.

They wobbled in surprise and repeated it. Tenn and the Jinglian parroted the same note back and forth, the same greeting, again and again.

Gaku watched them and his annoyance began to grow again. They were on a tight schedule, and he really didn’t want to waste any more time by being stuck on one word or phrase forever.

“Can we start?”, he tried not to sound like anything _but_ his annoyance, and both the Jinglian and Tenn flinched. Maybe it had been too harsh, Gaku thought, but he had to cancel out that slight fond feeling that had begun blooming in his chest at seeing Tenn in his element.

The plan for the next few meetings was to establish a ‘dictionary’ of simple words based on pictures, nouns and verbs that simply had to exist in both languages. It was based on structure and surroundings and some brain scans that had made Gaku determine that grammatical structures not unlike earth’s languages existed In the Jinglians’ language as well.

It would be the first step for them to actually communicate with the inhabitants of planet 8Da9H, and Gaku was really looking forward to it. He had prepared many, many slides that they could show the alien, and he couldn’t wait to see his work come to fruition.

So they started. Tenn had insisted that they didn’t need to record everything, because he would be able to accurately note down every combination of sounds they made, but Gaku didn’t want to take any chances, so there were a camera and microphones installed in the room.

The atmosphere on planet 8Da9H was different to earth’s natural atmosphere, or the artificial ones from mars, the moon, and every spaceship and space station, so they couldn’t spend too much consecutive time down here. Progress was going to be slow, and Gaku just wanted to be as quick and efficient as possible.

“But look Gaku”, Tenn said. “I already found out what ‘hello’ means.”

He looked too damn smug about it.

Gaku felt his eyebrow twitch.

“Let’s just begin”, he mumbled and started the slideshow, trying his best to ignore that this was probably the first real smile he had seen Tenn smile since he arrived here, and that it might not have been as smug and more of a genuinely happy smile than he wanted to admit to himself.

☆☆☆

Tenn was ignoring Gaku.

He was wearing those impossibly expensive high-tech headphones that broadcasted sound right into your brain (even though Gaku knew for a fact that Tenn also owned older ones, probably just as expensive, but those at least made actual sounds), and was looking at a holographic projection. Next to him stood a bowl of snacks that had no nutritional value and only existed for the satisfying noise they made when chewing them, untouched.

“What are you watching?”, Gaku asked.

Tenn flinched and ripped the headphones off his head. “Nothing”, he said, far too hastily for Gaku to believe him.

He took a look at the hologram.

It was a clip from an interplanetary video sharing platform. It was fairly popular, as Gaku could see when he looked at the view count. In theory everyone on mars had seen it. The title of the video that Tenn had been watching was “Best of IDOLiSH7 – Riku is cute!” together with a bunch of emoji.

“Wouldn’t have taken you to be one to like an earth idol band. Do you like this guy?”, he pointed at the redhead on the stopped hologram, who was probably singing at the moment, smiling into the audience happily.

“Of course I like him”, Tenn pouted. He was still mad that Gaku had caught and interrupted him. “He’s my brother.”

“Oh”, Gaku said. “Wait, can you say something like this so casually? Isn’t that some big music business secret?”

“Yes. You will be assassinated for knowing it”, Tenn took the bowl and munched on one of the colourful crackers.

Gaku reached for a pink one that would taste like artificial strawberry, but Tenn slapped his hand away. He clicked his tongue in response – this was getting annoying again. 

“Okay, maybe you won’t be assassinated. But only if you don’t tell anyone.”

Gaku had already pieced something together, a tale that was very sad, and probably closer to the truth than he wanted to believe, for everyone who was involved’s sake. But then again, this was the entertainment industry, he could never be too sure.  
He nodded: “Give me all the strawberry snacks and I won’t tell anyone.”

Not that he would’ve told anyone the other way, but Tenn didn’t need to know that.

The musician thought about the proposal a little, and then began picking out all pink snacks from the bowl.

Triumph drowned out the last of the annoyance that Gaku might have felt, as Tenn dumped a bunch of strawberry flavoured snacks in Gaku’s hands.

“I _will_ know if you tell anyone”, he said.

“Yeah sure”, Gaku’s mouth was pleasantly flooded with the too sweet flavour of artificial strawberry. “So are you gonna finish your cute brother compilation, or nah?”

Tenn hit his arm. It didn’t hurt.

☆☆☆

“So… your brother, huh?”

They were on the trip back from planet 8Da9H’s surface to the space station. It would usually take approximately half an hour, but today there had been a nasty storm that knocked them off their trajectory just before they had left the atmosphere, so now they were drifting in the orbit of planet 8Da9H, waiting for the station to be close enough for it to make sense to use their thrusters. According to the computers the shuttle would probably have to wait an additional twenty-five minutes, which meant that they would be stuck together for about an hour.

They had slowly been getting along better, even out of work, so this was a good time as ever to talk about themselves, wasn’t it?

The glare Tenn shot him made him realise that it wasn’t. It really wasn’t.

“What about my brother?”, he was on the defence. Gaku didn’t know how to deal with this Tenn.

“Well, what is he doing on earth in some idol band? I thought you were from the moon? Shouldn’t you be together or something?”

The flash of hurt in Tenn’s eyes hinted towards something far bigger than Gaku was expecting. It almost made him stop. But Gaku was stubborn and insensitive and most importantly an idiot, so he just continued.

“Is the whole moon story just a PR stunt and you actually abandoned your brother back on earth in search of the big fame?”

“Would you shut up?”, Tenn looked like he was about to cry.

Seemed like Gaku had hit a nerve. But Gaku, as previously stated, was an idiot with the average sensitivity of a starfish. He spoke his mind, always, without fail. Maybe he’d hate himself for his hot-headed reaction later, but in this moment, it didn’t matter to him.

“So I’m right? Does your brother even know that you look at what he does? What about the rest of your family? What about your parents? Did you leave them behind too?”

Without Gaku noticing, Tenn had curled up on himself, his knees pulled up to his chest, hands pressed to the helmet of his protective suit that was a requirement to wear on the planet’s surface.

Distress, Gaku observed, didn’t suit Tenn.

He reached out a hand, as if to touch the other, but the musician swatted his hand away.

“Don’t you think I’ve thought about all this?!”, Tenn snapped. There were tears at the corner of his eyes that threatened to fall. “Don’t you think my every waking moment is occupied with thoughts like that? Don’t your think that I’m concerned for my own _twin_? Of course it would be on my mind, especially since I regret not being able to solve the situation in any way other than leaving! But what would Mister Yaotome Gaku, genius scientist scouted by Humanity’s Space Bureau at age twelve, know about feeling like you abandoned your family, right?”

It was a low blow, to compare their situations like that. And even though Gaku wished he could just shoot back that it wasn’t alike at all, he couldn’t. Because they weren’t that different, he and Tenn. Because Tenn was right.

Instead of shooting back, Gaku felt his entire animosity leave his body like a balloon deflating.

Should he apologise? Actually that was a stupid question. Of course he should apologise. But was he ready to admit defeat?

He wasn’t, Gaku decided.

Leaning back in his seat, Gaku looked at the holo-screen displaying what their outside cameras were picking up.

The endless, velvety darkness of space, outshone by the soft purple of planet 8Da9H’s surface, illuminated by the rising star 9Fo8X.

Its light was colder than the solar system’s sun, at least in a way. Gaku couldn’t really describe it well, but he thought that he didn’t miss the sun. He hadn’t really missed his home either, when he left for the Bureau’s school. After all, he was able to easily call them or send them a video message, if he wanted to.

Not missing them hadn’t stopped him from feeling responsible for his parents splitting up and finally divorcing. He hadn’t had anything to do with it, and rationally he knew that, but he was still plagued with the ‘what if’s’, what if he had been there? Would they have gotten along better? Probably not, was the answer he had to give himself.

The only thing he had ever craved to remind him of home was and had always been… soba, he supposed.

Maybe that was the difference in their situations, Gaku thought. He had been allowed to miss and contact home. Tenn didn’t have a choice but to have a hard break, without any way to talk to his family ever again, whyever that was, but Gaku didn’t want to ask anymore. Tenn’s silent tears next to him hurt him too.

His gaze drifted from planet 8Da9H’s surface to deep space, searching for some dots of light that may or may not be the sun, and mars, and earth, and even the moon.

He felt sorry for Tenn, Gaku decided.

“Just… talk to your brother if you get the chance, yeah?”, Gaku said. “You’ll do yourself a favour. There’s no need for both of you to be in agony.”

A huff from Tenn, and a tearful smirk so fake that Gaku’s heart clenched traitorously. No wait, this was annoyance. He was getting annoyed again. Nothing else.

“Worried about me, old man?”

A glint of genuineness appeared in Tenn’s eyes, and Gaku decided not to explore any of these feelings anymore, and instead gave Tenn a friendly nudge with his elbow.

When they returned to the space station, Gaku felt Tenn’s gaze linger on him, before they both disappeared to their quarters, to get cleaned up.

☆☆☆

“You shouldn’t work while eating”, Tenn said and almost made Gaku choke on his food. He was indeed reading a report on a recent expedition of a part of planet 8Da9H where they hadn’t been before. He hadn’t gone with his colleagues because he had been busy with the dictionary.

“It saves time”, he mumbled around a spoonful of mashed potato.

“It’ll upset your stomach.”

“It hasn’t so far.”

“Still unhealthy. You should eat together with someone and talk to them.”

“If I’m talking, I can’t eat though.”

“It works, don’t worry. It will make you appreciate the food more as well.”

“The food here isn’t soba. I don’t need to appreciate the food.”

Tenn looked confused. “What’s soba?”

“You don’t know soba? It’s a really old dish, full of tradition. My grandpa has a restaurant on mars, and he says the recipe was from his ancestors from earth. They’re noodles, but also so much more.”

“Sounds good”, Tenn nodded. He sat down in the seat in front of Gaku. “Tell me more about mars.”

“Huh? Hell no. Haven’t you been there on tour before, Mister Music Prodigy?”, Gaku ate another spoonful.

“Not on mars, no. I’ve stayed on the moon ever since I left earth.”

“Well then hurry up and get to mars, so you can eat my grandpa’s soba.”

“Will you take me?”, Tenn asked, and Gaku felt the initial annoyance he had felt at both his meal and reading being interrupted coil around a new feeling like a poisonous snake, a warm and fuzzy feeling that had come to life with the pure request.

Shit, what was that feeling?

“Only after we finish out work here.”

“Sure. Let’s work hard then, shall we, Gaku?”

He wondered when they had become close enough to be on a first name basis. And agreed.

☆☆☆

“I don’t think this is going to work.”

Tenn’s voice startled Gaku out of the half-nap he had fallen into while taking a break from working. The book that the other had lent him and that he had been reading fell from his face, where it had been left when he had nodded off. It slipped off his body and landed on the floor with a thud. Who even used paper books nowadays? They were super rare. This edition was at least a hundred years old, if not older.

“What isn’t gonna work?”

“This”, Tenn showed him the work he had opened at his desk. A holographic synthesizer keyboard that was able to replicate any sound humans knew about, the video of their last session with the Jinglian, and the digital version of the sheet that Tenn took notes on every single session, cluttered with colours, instruments, expressions, feelings, and numbers. Gaku didn’t know how Tenn could work with it, but apparently it did the thing for him.

“Yeah? What about it?”

“The way the Jinglians produce the sounds is unlike the way humans do it”, Tenn said. “Even if we manage to create a dictionary and teach a human to understand Jinglian, they won’t be able to speak it. Our range isn’t big enough.”

“So not even you could do it?”

“That’s a flattering compliment, but no, not even I could do it.”

“Then we need something else for that.”

“Like a translation device that works both ways.”

Gaku stared at the book on the floor and picked it up again. It was worn and well-loved, probably third, or fourth, or maybe even fifth hand. It was weird and not something he had expected Tenn to enjoy reading, but it actually had just the thing.

“So we need a babel fish”, Gaku said.

For a second Tenn was quiet, but then he nodded. “That’s exactly what we need.”

“That actually makes everything easier”, Gaku nodded. “If we had a device like a babel fish that translates Jinglian into a human language and a human language into Jinglian. You’re a genius Tenn.”

“You are too, Gaku”, and Tenn smiled like he never had before. Like he was an open book, ready to be read by Gaku. And how he wanted to read that book, learn everything about it and keep it with him forever.

And Gaku supposed that maybe after all, geniuses didn’t have to be loners, and could work together to produce results, and maybe something else.

**Author's Note:**

> Some notes!
> 
> >initially this was gonna be a 5+1 format, but I scrapped that in favour of restructuring it like it is now. It’s still scenic, and the motif for the five things was “Gaku getting annoyed at Tenn” and that it also still very prevalent
> 
> >I spent hours thinking about how to make this language work. In the end I just established that it has similar structures as earth languages as a rule, because when you break it down, those aren’t anything other than random sounds aligned to form words
> 
> >Tenn has synaesthesia in this. I described it how my own synaesthesia works, even though Tenn’s is more intense and more precise than mine. The high-tech ‘headphones’ don’t trigger it (even though he doesn’t know why. I assume it’s because it stimulates the brain directly instead of the brain going through the process of having to interpret the soundwaves from the ears) so he uses those to ‘hear’ the ‘normal’ sound anyone else would also hear, without any distractions. When he composes he only uses the high-tech headphones at the very end, to check if the song he wrote is still good, even without ‘added senses’.
> 
> >who guesses which book Gaku is reading and which book the title is a reference to without googling will get a virtual pat on the back
> 
> If you want to talk to me you can do so on my [twitter](https://twitter.com/eins_kai)~
> 
> Thank you for reading!
> 
> -Kai


End file.
